"HI MOM GOD BLESS U!" can be seen stamped onto the snow-covered roof of an at-least nine-story parking garage in a photo the hospital posted on itsofficial Twitter account Monday. The "o" in "mom" was made into a smiley face, and the message spanned the width of the roof.

Angela Washek, a 26-year-old surgical nurse, said she and her fellow nurses saw four people on the roof of the parking garage Saturday night. She assumed they were just goofing around.

But around 1 a.m. Sunday, Washek noticed the message.

"It made everybody's night so much better, seeing a good message like that," said Washek, who's worked at the hospital for two years. "Sometimes we only see the bad side in healthcare. We don't get to see the good that we do sometimes."